why does car excelerate slowly?
car was running well on my way to work, but started to jerk and would not accelerate above 15mph. i know i need to replace spark plugs in back of engine and i am only firing on 4cylinders instead of 6
sounds like you answered your own question.
More likely to be something along the lines of an air metering problem. Spark plugs will generally wear down to little tiny nubs before letting you down. MAF? Is the "Check Engine" light flashing? Could be a fuel problem as well. I doubt replacing spark plugs will fix anything.
Search Ford Probe Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Ford Probe Experts